Boo

A group of teenagers spend a terrifying night in an abandoned mental hospital for Halloween, but things take a dark turn when they discover that it's home to a malevolent spirit and a vengeful serial killer who has been reanimating the dead. As bodies pile up and alliances are tested, the remaining survivors must fight for their lives against the forces of evil that have taken over the hospital. With its chaotic mix of horror elements, Boo is either a loving homage to "haunted house" cinema or one of the laziest horror movies made in 2005 - you decide.